Power Steering Failed problems of the 2006 Hyundai Azera

Trip computer returns to 00 without touching reset button, door lock sometimes does not open with transmitter. Trunk sometimes does not open with transmitter or interior trunk release. . Radio cuts off intermittently. Instrument panel light flickers, and engine will stall for an instant. Back window screen goes up and down by itself. Air conditioner came on without my pushing button. Warning messages will appear for few seconds "check engine", "abs failure", etc. Twice took car to Hyundai service department. Told they cannot fix anything unless these events are happening when I bring in car. Aside from these fairly minor problems, the steering wheel locked or power steering failed while driving. . The service department did find an oil leak and replaced hose. Replaced fuel level sender and driver door module. But the electric problems continue. . I am worried that electric and steering problems will cause a serious accident.